/* Copyright (c) 2010 Google Inc.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package com.google.wave.api;

/**
 * A class that represents a property filter for element, that can be used when
 * when searching for an element inside a blip.
 */
public class Restriction {

  /** The key of the property. */
  private final String key;

  /** The value of the property. */
  private final String value;

  /**
   * Creates an instance of {@link Restriction} for a property with the given
   * key and value.
   *
   * @param key the key of the property to restrict.
   * @param value the value of the property to restrict.
   * @return an instance of {@link Restriction}.
   */
  public static Restriction of(String key, String value) {
    return new Restriction(key, value);
  }

  /**
   * Constructor.
   *
   * @param key the key of the property to restrict.
   * @param value the value of the property to restrict.
   */
  private Restriction(String key, String value) {
    this.key = key;
    this.value = value;
  }

  /**
   * @return the key of the property to restrict.
   */
  public String getKey() {
    return key;
  }

  /**
   * @return the value of the property to restrict.
   */
  public String getValue() {
    return value;
  }
}
